Glenn Beck, the rightwing US broadcaster and Tea Party favourite, has compared those who were massacred on the Norwegian island of Utøya to the Nazi party's youth wing.

"There was a shooting at a political camp, which sounds a little like the Hitler youth, or, whatever. I mean, who does a camp for kids that's all about politics. Disturbing," said Beck on his syndicated radio show.

The comments were condemned by Torbjørn Eriksen, a former press secretary to Jens Stoltenberg, Norway's prime minister.

Eriksen described the comment as "a new low" for Beck, telling the Daily Telegraph: "Young political activists have gathered at Utøya for over 60 years to learn about and be part of democracy, the very opposite of what the Hitler Youth was about. Glenn Beck's comments are ignorant, incorrect and extremely hurtful."

Sagging ratings, a string of damaging remarks and an exodus of advertisers combined earlier this year to end Beck's tenure on the US cable network Fox News.

A campaign to pressure advertisers to boycott the pundit's daily slot had been gathering pace, while Beck was embroiled in battles erupting from his frequently aired conspiracy theories involving individuals ranging from the financier George Soros to Barack Obama.

His denunciation of Soros included reference to his wartime childhood in Hungary. In remarks that were decried as "monstrous" by Jewish groups, the broadcaster claimed: "Here's a Jewish boy helping send the Jews to the death camps."

However, his latest comments about the "disturbing" nature of political youth camps may come as a surprise to Beck's followers in the Tea Party movement.

The anti-tax, anti-immigration movement has been holding summer camps in states including Florida and Missouri where children have been taught a curriculum based on God, the US constitution and "the defence of economic liberty".